The present invention relates to an adjustable load bolt adapter bracket assembly particularly adapted for use with a sway brace in securing a bracing element between a fluid pipeline and a fixed structure to anchor the pipeline to the structure. Sway braces are commonly used in building structures for securing numerous types of fluid supply lines to the structure to brace the lines against damaging movement such as could result from a seismic disturbance. An example of such a sway brace is found in U.S. Pat. No. 4,697,770. As seen therein, the sway brace secures a fluid supply line to a joist or other building structure by means of an elongated tubular bracing member which is held adjacent one of its ends by the sway brace and is fasten at its other end to the joist by a pair of bolts or other approved fastening members.
Recent changes in building codes have required additional securement of the bracing member to the structure. This has been achieved through the use of an adapter plate having three fastener receiving apertures therein. The plate is positioned over the mounting bracket by which the bracing member is secured to the structure or, in the case of the above patented structure, over the flattened end of the bracing element, such that two of the apertures in the plate are aligned with the apertures in the bracket, leaving the third aperture in the plate in axial alignment with the super imposed apertures of the plate end bracket. Through this configuration three bolts or other securement fasteners can be used to secure the bracing member to the building structure, increasing the strength of the attachment. Alternatively, an adapter plate having four apertures can be employed with the bracket to provide two additional fastener receiving apertures for applications requiring even additional attachment support.
While the use of such adapter plates has heretofore satisfied code requirements, they are subject to relative movement with respect to the brackets in the event of eccentric loading during a seismic disturbance due to the lack of any positive engagement between the plates and the bracket. In addition, such plates are configured so as to extend from the rearward end of the mounting bracket. As the building joists or other fixed members to which the mounting bracket and adapter plate are to be secured are often somewhat narrow and angularly disposed with respect to the central axis of the mounting bracket when the bracket is positioned thereon, there can be insufficient surface area to accommodate the rearwardly projecting bracket. The load bolt adapter bracket assembly of the present invention not only provides the positive engagement between the bracket and plate lacking in the adapter plate/mounting bracket combinations heretofore available, but allows for both extended and lateral parallel mounting of the adapter plate with respect to the mounting bracket to provide a variable footprint and thus better accommodate the available mounting space on the joist or other mounting surface while continuing to minimize any relevant movement between the mounting bracket and plate in the event of a seismic disturbance.